For vehicles that are to be used on bad conditions such as beaches, river beds, streams, muddy roads and deserts, the tires of the vehicles are required to have specific designed tread profile so as to have better traction.
Those tread profiles generally have offset design, namely, asymmetric tread profiles with higher traction while turning at high speed.
Two conventional tires with asymmetric tread profile known to applicant are disclosed in U.S. Pat. Nos. 4,840,210 and 5,971,048, the former patent discloses a tire whose maximum outer diameter is located at a distance “L” from the center line of the tire section and the value of “L” is 0.05 to 0.30 of the width of the tire section, the ratio of the diameter “d1” of the outer shoulder and the diameter “d2” of the inner shoulder are 0.98 to 1.00.
The latter patent discloses a tire with an inner shoulder profile and an outer shoulder profile, each shoulder profile has a shoulder drop which is the distance from the point of maximum tire diameter to the point of the shoulder at the edge of the shoulder profile. The shoulder profile is asymmetric and has its point of maximum tire diameter offset in the axial direction of the tire from the center line of the tire section in the direction f the inner shoulder. The shoulder drop of the outer shoulder is greater than the shoulder drop of the inner shoulder. Both of them do not disclose specific size relationship of the tread.